1. Field
The present invention relates to a technology for evaluating network performance.
2. Description of the Related Art
There has been an active evaluation method that evaluates the performance of a network by actually circulating test data (packet) with respect to the network to be evaluated, intended to evaluate the performance (such as packet loss rate) of the network.
For example, in active evaluation, as illustrated in FIG. 20, a transmission device and a reception device are disposed as a measurement device (e.g., probe and server), at any measurement location in the network that the performance is evaluated. Between the transmission device and the reception device, the transmission device actively generates and transmits test data, and the reception device then receives the transmitted test data and evaluates the performance of the network.
Japanese Laid-open Patent Publication No. 2005-269170 discloses a conventional technology of measuring transmission quality of voice packet in the internet protocol (IP) phone network by an active evaluation.
In the conventional technology, as described below, active evaluation cannot be performed without incurring a negative impact on the actual network operation.
FIG. 20 is a schematic diagram for explaining the conventional technology. For example, as illustrated in FIG. 20, if the conventional active evaluation is performed on the network actually being operated, a negative impact such as discarding of real data is incurred on the service actually being operated. Giving a specific example, when the maximum bandwidth of a network is exceeded by test data (packet) generated by the conventional active evaluation, real data is discarded. In the conventional active evaluation, the evaluation needs to be carried out, while the service in operation is stopped (e.g., by temporarily stopping the service). Accordingly, monitoring cannot be performed periodically while the service is in operation. With the conventional technology, active evaluation is not performed without incurring a negative impact on the actual network operation.